Caesium azide

Caesium azide or cesium azide is an inorganic compound of caesium and nitrogen. It is a salt of azide with the formula CsN₃.

CsN₃ adopts the same structure as KN₃, RbN₃, and TlN₃, crystallizing in a tetragonal distorted caesium chloride structure where each azide ion coordinates to eight metal cations, and each metal cation coordinates to eight terminal N centers. When heated to 151 °C, it transitions to a cubic structure.

Caesium azide can be prepared from the neutralization reaction between hydrazoic acid and caesium hydroxide:

CsOH + HN₃ → CsN₃ + H₂O

Caesium carbonate can also be used as the base:

Cs₂CO₃ + HN₃ → CsN₃ + CO₂ + H₂O

Caesium sulfate reacts with barium azide to form insoluble barium sulfate and caesium azide:

Cs₂SO₄ + Ba(N₃)₂ → 2CsN₃ + BaSO₄↓